Aqueous alkali containing hair relaxing or straightening compositions are known in the art. Such compositions usually have a pH of about 12 to 14 due to the presence of a water-soluble alkali or alkaline material such as sodium hydroxide, and are most frequently formulated as emulsified or creamy, viscous preparations so that once applied to the user's hair, they will not drip onto the skin or into the eyes.
Hair relaxers are generally supplied as "with base" or "no-base" formulations. A "with base" formulation is generally supplied in two packages; one containing the oleaginous base and one containing a thickened aqueous composition of alkaline materials. For these products with a base, the oleaginous base is first applied as a protective layer to the user's scalp and hair followed by application of the thickened aqueous alkaline material which then relaxes the hair. No-base formulations are one package systems in which the aqueous and oleaginous materials are co-emulsified. The no-base formulations are applied directly to the user's hair without a prior pretreatment of the scalp.
While great strides have been made in formulating no-base compositions such that proper hair shaft penetration by the alkali is achieved along with minimal scalp injury, to thereby improve safety, and also by the incorporation of conditioning agents to leave the hair with a better feel after such a treatment, most products nevertheless separate or de-emulsify on aging. The loss of stability or de-emulsification results in a product having two distinctly visible phases. While such destabilized products may be used, they must be remixed before using in an attempt to assure the user that the active ingredients are at the proper levels in the portion being used. However, such mixing, even though done thoroughly by hand, does not in fact give the user consistent results with such products. Product destabilization and resulting consumer dissatisfaction are among the chief complaints in the industry.